It's not "hard" to put stuff in or take it out. It's easy to get samples out. But, I have found that putting the samples back in the carboy has a tendency of making bubbles, and maybe providing more oxygen than I would like to the batch. In general, I am getting the idea that its best to keep sample-taking to a minimum.
I'm thinking of trying BDC DYF method: http://www.gotmead.com/forum/showthread.php?t=14437
I'm thinking of trying BDC DYF method: http://www.gotmead.com/forum/showthread.php?t=14437